Study on Haemodynamic Response to Laryngoscopy and Intubation using McCOY and Macintosh Laryngoscopes: A Comparative Approach

Abstract

Introduction: Laryngoscopy and endotracheal intubation are known to cause increase in arterial blood pressure, heart rate and may be associated with various dysarythmias. This study is done to compare the hemodynamic changes with McCOY laryngoscope and Macintosh laryngoscope in 120 patients who were divided into 2 groups. Methods: A positive correlation has been demonstrated between force exerted at laryngoscopy and patient's height, weight, body mass index (BMI) and presence of maxillary incisors but it was seen that effect of these factors on force exerted with the McCOY blade is not as important as with Macintosh blade. So this study was done to compare the hemodynamic response to laryngoscopy and intubation using McCOY and Macintosh laryngoscope in stress attenuation. Results: Maximum increase in heart rate from the baseline after laryngoscopy in group 2 and a least rise in heart rate from base line in group 1.Group 1 has 9 % increase in heart rate from basal value. Group 2 has 22 % increases in heart rate from basal value. Group 1 has 6 % increase in  Systolic BP from basal value Group 2 has 27 % increase in Systolic BP from basal value. Rise in Plasma adrenaline after laryngoscopy was not observed in Laryngoscopy with McCOY blade. Conclusion: McCOY laryngoscope produces significantly less in Hemodynamic parameters when compared with Macintosh blade.So this non­pharmacological intervention of McCOY blade can be utilized as a tool for obtunding hemodynamic responses to laryngoscopy and intubation